Can't access Android pydio app due to certificate issue

I issued a certificate from sslforfree for use in pydio.
The installation is complete and everything seems to be fine.

However, when I enter the URL in the Android application and hit connect, display this message.
“Unable to verify server certificate”

enter ID PASS in the login window and Click connect and display message.
“could not get authentication token”

Even if you select your own certificate during cells install, you cannot connect from Android.

Can’t I use https in the pydio andorid app?